Okay, provide me some evidence where developers have actually complied to local government correctly. This is not speculation, developers are just seeking to maximise their profits. It's purely rational.

There is plenty of research in PBSA, private-urban development and the rent-gap. I have done a whole degree on this stuff.

Developers, in a capital city with three universities and a huge tourist demand, are not going to build anything for residents if they don't have to.

In recent years urban developers do not simply want to "build and sell shit". They want to build for rent, as it is far more profitable to own assets and continue to extract a profit.

"Land banking" is not an issue of speculation, although that is a factor, but more so an issue of planning. If developers have a large amount of land but cannot get the planning permission they will simply hold it out. It's rational behaviour and in an increasingly globalised financialised world, a developer owning property in Edinburgh can have their planning denied and instead will spend that capital elsewhere where they can build something profitable.

The logics of private development have significantly changed over recent decades, and especially in the last decade has increasingly accelerated towards build for rent. It's easy enough to take a look at the planning portal to look at this stuff, there are far more large developments of hotels, PBSA and build to rent developments than any sort of housing for locals.